Introduction: Epiploic appendagitis is a rare etiology of abdominal pain with incidence estimated to be between 2–7% of patients suspected to have acute diverticulitis and in 0.3–1% of those suspected to have acute appendicitis. The pathophysiology is secondary to an ischemic infarction of the small fat-filled, serosa-covered outpouchings located on the external surface of the colon projecting into the peritoneal cavity (epiploic appendage) which can be caused by torsion or spontaneous thrombosis of the central draining vein of the epiploic appendage. The most common cause is acute torsion when the appendage is long and large. It can present with abdominal pain at the location of infarction (more commonly on the left side), emesis, low grade fever, leukocytosis with neutrophilia and elevated inflammatory markers. We present a case of epiploic appendagitis initially diagnosed as acute diverticulitis.

Case discussion: A 32-year-old male presented with right lower quadrant abdominal pain of progressive onset within 3 days. Pain described as sharp, non-radiating, rated 8/10, initially intermittent then constant, with no relation to food intake. He had associated nausea. No fever, chills or change in bowel habits. Vitals were stable on admission. CBC was remarkable for leukocytosis with neutrophilia. Otherwise all laboratory results, including lipase and lactic acid, were within normal limits. CT abdomen and pelvis with contrast was read as an acute inflammatory process in the right colon localized to the hepatic flexure, no abscess or free fluid which may be secondary to diverticulitis. In the setting of inconsistency between pain location and the imaging findings, the CT results were further discussed with radiology. After thorough revision of the imaging, the findings were diagnosed as epiploic appendagitis. Radiology revision of imaging described a round to oval-shaped fat density with periappendageal fat stranding. General surgery was consulted due to initial concern for acute diverticulitis vs appendicitis. After imaging review, general surgery was in agreement with the diagnosis of epiploic appendagitis. The patient was given pain medication with resolution of abdominal pain and was discharged on Ibuprofen.

Outcomes/Follow up: Epiploic appendagitis is a self limiting condition and the general management is conservative with NSAIDs and a short course of opioid analgesics if needed. Surgical management is reserved for patients whose symptoms fail to improve with conservative treatment. Historically, it can be mistakenly diagnosed as acute diverticulitis or acute appendicitis depending on the location of pathology. Abdominal CT is diagnostic for epiploic appendagitis and the classic finding is described as an oval-shaped, fatty paracolic mass with thick peritoneal lining and periappendageal fat stranding, but commonly it requires imaging re-evaluation with radiology for correct diagnosis. Knowledge of this uncommon etiology of abdominal pain is important given CT imaging features is the main differentiating factor from acute diverticulitis and appendicitis.

References and Resources

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